Cryogenic Performance and Reliability of GaAs CHFETs

GaAs CHFETs (complementary heterostructure field effect transistors) were characterized before and after stress testing at both room temperature and in cryogenic conditions. Various values of drain and gate voltages were used for stress conditions, and the effects of temperature on both performance and reliability were examined. A decrease in drain saturation current is observed below 150 K as well as an exponential decrease of gate leakage with decreasing temperature. Parametric degradation that follows a log-log relationship was observed under all stress conditions. For high electrical stress, the degradation was found to be worse at cryogenic temperatures